TCP Retransmission requests from IPTV Server and TCP Dup Ack Requests from Client

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Server address ( 208.240.190.100) and client ( 210.220.160.48). We are having some problem in the IPTV traffic. It stucks sometimes and sometimes there is a delay in video . Below mentioned is the tcp dump which i took at server side . In this , we can see that there are lots of TCP retransmission requests coming from Server and Client is also sending TCP Duplication Acknowledgement request. Can someone please take a look at the below mentioned packet capture and let me know whether the problem exist ? as is it at the client side or on the server ? as why server is retransmitting the packets .

I did a continuous ping from client to server but could not see any delay or time out.

234 0.672953    210.220.160.48   ---------  208.240.190.100      TCP         60 51977 → 80 [ACK] Seq=231 Ack=97409 Win=64240 Len=0

235 0.672958    208.240.190.100 ---------   210.220.160.48               TCP         2974   80 → 51977 [ACK] Seq=114929 Ack=231 Win=41808 Len=2920 [TCP segment of a reassembled PDU]

236 0.679994    210.220.160.48    ------------       208.240.190.100    TCP   60       [TCP Dup ACK 231#2] 33042 → 80 [ACK] Seq=1 Ack=94901 Win=64240 Len=0

237 0.679998    208.240.190.100   ----------    210.220.160.48         HTTP        1514      Continuation

238 0.689851    210.220.160.48     -----------      208.240.190.100         TCP   60      [TCP Dup ACK 231#3] 33042 → 80 [ACK] Seq=1 Ack=94901 Win=64240 Len=0


239 0.689855    208.240.190.100   ------------- 210.220.160.48          HTTP  1514  [TCP Fast Retransmission] Continuation

240 0.693000    210.220.160.48      ------------       208.240.190.100      TCP     60          51977 → 80 [ACK] Seq=231 Ack=100329 Win=64240 Len=0

241 0.693004    208.240.190.100    ------------ 210.220.160.48            TCP   2974    80 → 51977 [ACK] Seq=117849 Ack=231 Win=41808 Len=2920 [TCP segment of a reassembled PDU]

242 0.699995    210.220.160.48     ---------------  208.240.190.100 TCP       60    [TCP Dup ACK 231#4] 33042 → 80 [ACK] Seq=1 Ack=94901 Win=64240 Len=0

Server is also showing some malformed packets in errors of wireshark . Below mentioned are the errors on server side wireshark capture .

1884 TCP: [TCP Fast Retransmission] 80 → 51977 [ACK] Seq=1053709 Ack=231 Win=41808 Len=1460[Reassembly error, protocol TCP: New fragment overlaps old data (retransmission?)]

2335 TCP: [TCP Fast Retransmission] 80 → 51977 [ACK] Seq=1308554 Ack=461 Win=41808 Len=1460[Reassembly error, protocol TCP: New fragment overlaps old data (retransmission?)]

Please help me regarding it that how i can resolve this issue ?

Thanks